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Summary Recently increased attention has been given to the utilization of agricultural waste products to produce food, feed, fertilizer and as a raw material in certain industries. Such utilization could not only help maximize available resources but at the same time minimize waste disposal problems. Nutritional and oil characteristics of different seeds were investigated. On a dry basis protein contents of 43, 34, 16.1 and 36.9% and oil contents of 19, 50.6, 35.9 and 25.7% were found in maple, pumpkin, citrus and apple seeds, respectively. Determined food energy values averaged 626 kcal/100 g (26.2 kJ/g). The seeds were found to have valuable amounts of essential minerals. The major fatty acid composition was 18 : 2 (linoleic) at concentrations of 39.1, 58.9, 31.9 and 45.6% and total saturated fatty acids of 16.8, 19.7, 42.8 and 12.4% and cis, cis-PUFA contents were 34.1, 46.8, 19.8 and 45.6%, respectively, for maple, pumpkin, citrus and apple; no measurable amounts of trans fatty acids were found.

Various physical properties of bread made with an emulsifier as a replacement for shortening were assessed. Sodium stearoyl lactylate (SSL) at 0·375% (w/w) of the flour weight produced bread comparable in quality to bread made with shortening. Specific volumes of greater than 6 ml/g and compression values of 176–189 g/force after a 168-h storage at room temperature (24 ± 1°C) were obtained.

A good-quality white loaf of bread or rolls can be baked by substituting liquid vegetable oil (canola, soya and palm) for the standard shortening,i.e. lard, tallow or partially hydrogenated vegetable shortening. Canola oil and soya oil produced lower specific volumes of 5.56 and 5.55 cm3/g and higher softness indices when used with mono- and diglycerides only. Palm oil and lard produced specific volumes of 6.33 and 6.15 cm3/g and lower softness indices with mono- and diglycerides. When a blend of surfactants consisting of mono- and diglycerides and sodium stearyl lactylate (SSL) was used at 0.5% of flour weight, palm, canola, lard and soya gave comparable results in specific volume and compressibility. Rolls baked with the same fats and oils, and addition of ethoxylated stearic acid (MYRJ 45H) or a blend of MYRJ 45H and SSL, all gave good specific volumes ranging from 6.92 to 7.27 cm3/g and a softness index range of 0.71–0.86 and 0.68–0.86 after 48 and 96 h of storage. When a proper surfactant is used, good-quality bread and rolls can be baked with liquid vegetable oil. Furthermore, the usage level of liquid oil can be cut by approximately 30% in comparison to lard or shortening while still maintaining quality.

Luffa seeds (L. acutangula), a member of the Cucurbitaceae family, were investigated for their potential nutritional and oil characteristics. The yield of seeds from the fruit was 33·5%, while the kernel was found to possess 50% of the seed weight. The protein and fat contents of the kernel were 39% and 44%, respectively, and on a moisture and fat-free basis the kernel's protein content was 74·6%. The fatty acid profile indicates that the glycerides of oleic and linoleic acid constitute 68% of the total kernel oil. Iodine value, saponification value and acid value were 99·5, 190·8 and 10·5, respectively. The maximum melting and freezing points were −3 and −10°C, respectively. The seeds were also found to be a good source of certain amino acids, phosphorus, iron and magnesium.

Supplementation of pizzas and date bars with different protein concentrates was found to increase their protein content significantly, but the addition of a yeast protein concentrate (SCP) derived from petroleum via alcohol was found to increase the nucleic acid content of the fortified formulations linearly with the amount of added SCP. The consumption of a total of 30 g of SCP via the fortified food for 3 weeks increased levels of uric acid in serum an average of 8 mg/100 ml and in urine up to 1210 mg/24 h. Two weeks after termination of the yeast intake, both values dropped to near-normal levels.

The quality and shelf-life of fresh eggs were studied under simulated climatic conditions as found in Kuwait. Three groups of eggs (unwashed, washed, and washed and oil treated) were used. The treated eggs were stored at 5°, 25°, 37° and 42°C. Internal and external quality and sensory evaluation of the eggs stored up to 75 days were determined. The quality of the unwashed and washed eggs stored at 37°C and 42°C deteriorated rapidly while the wash and oil treatment extended shelf-life but decreased in quality to C over a period of time. The percent weight loss in the oil treated eggs at all temperatures was about 0.6% while the washed and unwashed lost more depending upon the temperature and storage time. All parameters studied for interior quality showed that oil treated eggs were significantly better than untreated eggs even at 42°C. Sensory evaluation on boiled eggs indicated that changes in flavor and overall quality for untreated eggs stored at high temperatures were obvious while little change in texture was observed. It was concluded that under Kuwaiti conditions eggs should be oil treated directly after collection and stored at or below 25°C so that the quality and shelf-life can be extended significantly.

A sample of 1,134 Kuwaiti (K) and 1,444 non‐Kuwaiti (NK) households in Kuwait was chosen at random to obtain information on food and nutrient availability in the household deduced from food purchases during one week. The data were studied according to income and taking into account households composition. Food available among NK was higher than in K households but was, on the average, abundant among the most privileged and adequate among the poor in both groups with respect to energy and protein. Nevertheless, K households which had a larger number, spent, on the average, a higher proportion of their income to buy food than NK families. Kuwaiti households purchased more cereals, sugars and sweets and fish than NK households. With increased income, purchases of most food groups, especially of protein‐rich products, increased in both groups, but in K households cereal purchases declined. In spite of adequate dietary availability, low income families in both groups had poor diets, especially with respect to ...

A mechanical tester with punches of different sizes and shapes was used to determine the effect of penetration speed, penetration depth, and gelatin concentration on the resistance of gelatin gels to penetration. Penetration speed in the range of 0.04–0.12 cm s-1had no significant effect on force readings. A straight line relationship existed between the square of gelatin concentration and penetration force. Depth of penetration was found to be an important factor in the measurement of the mechanical behaviour of the material. Coefficients of determination showed a high correlation between punch shape, circumference, depth of penetration, gelatin concentration and force readings.

All-purpose wheat flour and all-purpose wheat flour fortified with 6% soy flour; 2, 4 and 6% single cell protein (SCP) were used. Protein quantity was increased significantly in both flour and cookies. Sensory panel evaluations were conducted for flavor, texture and overall acceptability of cookies, and objective evaluation of rheological properties were made with the farinograph and shear-press on doughs, and shear-press on cookies. Fortification with SCP at all levels altered all the sensory parameters significantly, but fortification with soy flour altered only cookie texture. Fortification with both SCP and soy flour significantly decreased the “spread factor” quality. Correlations between panel texture scores and texture parameters from the farinograph or the shear-press were not significant. However “Consistency” and “Elasticity” obtained from farinograms were significantly increased due to the high level of fortification by SCP and soy flour, and the same results were found in “Viscoelasticity” obtained from the shear-press. Also, the determinations from both instruments showed that the tolerance to kneading was significantly reduced as a result of the fortification. Adhesive properties of dough as obtained from texturegrams were significantly increased due to the 5% SCP and soy flour fortifications. The variations of textural characteristics were highly predictable from texture parameters of doughs as obtained from both instruments. Thus the coefficient of determination (R2) of crispness and hardness as measured by the shear-press were 0.987 and 0.999 when farinogram parameters were used, and 0.999 and 0.997 when texturegram parameters were used as independent variables.

Ten different formulations of beef patties were processed to contain 20–50% fat from lean beef containing not more than 7% fat and beef fat consisting of not less than 90% fat and were extended with different levels of textured soy protein (TSP) at 5, 10 and 20% and single cell protein (SCP) at 2.5, 5 and 7.5%. The patties were stored at −18°C for 6 months. Sensory quality evaluation showed that patties with 80% lean and 20% fat and patties with 40% lean, 40% fat and 20% TSP were the least acceptable, but lower levels of TSP and SCP addition were found to improve panel rating. A 17% increase in protein content and a reduction of about 13.5% in fat content was observed due to TSP and SCP incorporation. An average cooking loss in the different formulations was 33%, addition of protein extenders was found to reduce cooking loss by about 22% while fat loss averages 30.2%. A reduction of 21.1% of 18:1 and a reduction of approximately 18.7% of total FAME and 32% cholesterol were observed due to the addition of TSP and SCP.

The textural and sensory qualities of reduced-calorie cakes prepared from non-shortening batters in which sucrose was partly replaced with sorbitol or poly-dextrose (with the addition of carboxymethylcellulose or microcrystalline cellulose to the latter) was studied. The batters were treated with different types and concentrations of emulsifier (Tandem 22H, Atlas A and MD-SSL). At the 30% replacement of sucrose with 1.5% or 3.5% (on flour weight) of Tandem 22H or Atlas A, the cakes were of an acceptable quality. Higher levels of emulsifier treatment further enhanced the aeration capacity of the batters, but impaired the overall quality of the final product. The emulsifier MD-SSL was found to be less suitable under the given conditions of cake baking because of the excessive aeration of batters. With cakes of acceptable quality, the calorie value reduction was in a 15 to 23% range compared with a standard full-calorie cake.

Some current dietary habits, food preparation methods and foods consumed by Kuwaiti citizens are described based on data collected from 500 adults of different education and income levels. The data show that while some traditional food habits are adhered to, others are giving way to western influences. Wheat is the main staple, followed by rice; mutton and lamb are preferred over beef; but chicken and fish are also consumed. Diluted yogurt (roob) is traditionally ingested during lunch, which is the main meal. Fresh fruits and vegetables are readily available, but their consumption is limited by purchasing power. Carbonated beverages, coffee and tea are consumed frequently and sugar utilization is high. Some food preparation practices have different implications on nutrient values of food. In cooking, rice is soaked in warm water for a few hours and then the water is discarded; meat and vegetable mixtures may be boiled for a long time. Such food preparation methods tend to destroy valuable nutrients; but p...

The protein content of many food products may be enriched by the addition of protein concentrates. Textured vegetable protein (TVP) and single cell protein (SCP) were added in varying amounts to a pizza formulation and stored at -20°C until used. The fabricated pizzas were analyzed for amino acids, total fat, fatty acids, sterols, water, protein, ash and cis, cis-methylene interrupted polyunsaturated fatty acids. The addition of TVP and SCP increased the protein content by an average of 18%. Certain amino acids, such as lysine, arginine, leucine and threonine, were significantly increased with the addition of TVP and SCP. The fat values were generally lower in pizzas with TVP and SCP, and the ash content increased. The moisture content ranged from 46 to 49%, except for the “beef + 5% SCP in crust” which was 41%. The fatty acid and sterol profiles were generally very similar.

The countries of the Arabian Gulf are hot and arid and both water and agricultural resources are strictly limited. The direct use of sea water in pickle processing was investigated. Different vegetables were fermented using brines prepared from filtered sea water, filtered and boiled sea water and distilled water. Average salt concentration of sea water was found to be 4%, which is the required initial salinity for vegetable fermentations. The calcium and magnesium content of sea water was found to improve firmness and colour of the pickled products. The rates of growth of the micro-organisms in the different brines did not vary and the final pH of the brines was ∼3.8. Average titratable acidities of 1% were obtained. No Pb, Hg of faecal coliforms were detected in the pickled products and an average total coliform count of 2613 ml −1 in the brines was observed. Sensory quality evaluation of the pickled products showed no significant difference between treatments.

Eleven varieties of Ontario grown soybeans were analyzed for protein, phosphorus and moisture content. The beans were processed into soymilk and bean curd prepared by coagulation with calcium chloride. Curd and protein yields were determined. Calcium chloride, sulfate and acetate were satisfactory for curd precipitation, but calcium citrate was not. Hardness of the curd was measured by compression in the Instron Universal Testing Machine. Rheological properties determined by creep testing included instantaneous and retarded elasticity as well as viscous flow. Moisture content of the bean curd is an important variable influencing the rheological properties.

Three different types of punches were used to test fat consistency in a penetration test: Bloom, Kruisheer and den Herder and a set of flat-end cylindrical punches. The use of Bloom type punches did not give useful results because there was no distinct yield point in the force-distance curves. With both Kruisheer and den Herder and the flat cylindrical punches a definite yield point was obtained. The relationship between punch area and force was a straight line going through the origin with normal and soft margarines. The relationship between punch perimeter and force was not linear. The effect of penetration speed and the relationship between the nature of the curves and the physical structure of the food is discussed. It was concluded that penetration tests of products such as normal and soft margarine with a weakly bound network structure involve flow as the major factor.

This study was undertaken to investigate the effectiveness of activated carbon and silica in removing the degradation products present in used frying oils. Two batches of canola oil were treated with mixtures of activated carbon and silica. Three levels of activated carbon (3%, 6%, 9%, wt/wt) were blended with three levels of a silica compound (2%, 4%, 6%, wt/wt) in all nine possible combinations. Oil 1 was prepared by continuous heating in the lab, and oil 2 was obtained from a small potato-frying operation. For each treatment combination of silica and carbon, the average percent decrease for acid value, peroxide value, photometric color, polar compounds, saturated carbonyls and unsaturated carbonyls was 53.9%, 39.4%, 38.3%, 27.5%, 54.0% and 27.3%, respectively, for oil 1, and 51.1%, 53,5%, 49.7%, 16.3%, 58.9% and 39.0%, respectively, for oil 2. The levels of oleic, linoleic and linolenic acids decreased by 28%, 33% and 35%, respectively, following heat treatment but were shown to increase by 1 to 5% after adsorbent treatment. The yield of treated oil ranged from 56 to 83%.

Dates are among the major food staples in the oil-rich but food-poor region of the Persian Gulf. Dry dates are a typical “empty calorie” food, containing over 80% carbohydrates, but only about 3% protein. By adding yeast protein producedfrom petroleum, and other inexpensive nutrient supplements to surplus low cost dates and date wastes, date bars were produced having a high acceptability, protein and fat levels of 10%, and two-to-threefold increase in protein bioavailability, and several of the B-vitamins and minerals. Retention of sensory quality, and nutrient quantity and/or bioavailability was affected by time-temperature of storage with only minimal effect when stored at or below 5dC for 6 months.

A simple inexpensive texture test system is described which is suitable for quality control applications. The apparatus is constructed from a drill press stand, a mechanical force gauge and a test cell. The effect of different operators and sample thickness was investigated using apple and potato as test material. The performance of this system was compared with that of the FTC Texture Press (Kramer Shear Press) in the testing of several foods.

Different agricultural seeds: apple, citrus, lufa, maple and pumpkin have been investigated for their nutritional potentials as food and feed components. The protein and fat content on a dry basis of the different seeds ranged from 16–43% and 19–50%, respectively. Food energy values averaged 22 Kj/g (526 KCal/100 g). Calcium and phosphorus were in the range of 0.06–0.48 and 0.25–1.05%, respectively. The fatty acid composition showed that 18:1 and 18:2 was the major component at concentrations of 40.1, 25.9, 24.3, 37.9 and 21.8 and 45.8, 30.7, 43.7, 39.7 and 58.5, respectively, for apple, citrus, lufa, maple and pumpkin. Amino acid profiles of the seeds indicated that the seed contains all the essential amino acids in a proper balance with apple and pumpkin containing 0.78 cystine. The methionine content of pumpkin is 1.35% and lysine contents of 0.81, 0.57, 2.25, 0.69 and 2.41% for apple, citrus, lufa, maple and pumpkin, respectively.

The use of date juice as a substrate for single cell protein production was investigated. Four strains of Saccharomyces cerevisiae and two strains of Candida utilis were examined as possible production cultures. The criteria used for screening the organisms were total cell count, total protein and decrease in soluble solids. S. cerevisiae ATCC 4111 gave the highest protein and cell production. The optimum substrate concentration was 4 - 5% soluble solids. At this concentration, ∼55% of the sugars was utilized. Cell mass after 12 h fermentation was 4.86 g l−1. The harvested and freeze-dried cells contained 8.6% nitrogen. The best combination of nutrient supplementation was found to be 0.25% (NH4)2HPO4 and 0.1% FeNH4(SO4)2; addition of MgSO4 and (NH4)2SO4 did not increase cell production.

Watermelon (Citrullus vulgaris) and grape (Vitis vinifera) seeds were investigated for their nutritional quality and oil characteristics. The yields of seeds on an as is basis (edible portion) were 1.6 and 1.8% for grape and melon, respectively. The melonseed on a dry weight basis consisted of 53.6% testa and 46.4% kernel. The crude protein, fat and fiber content were 16.4, 23.1 and 47.7% for melon and 8.2, 14.0 and 38.6% for grape (dry weight basis). Both seeds were found to contain significant levels of Ca, Mg, P and K. The fatty acid profiles showed an unsaturated fatty acid content of 76.1% for melonseed oil and 88.6% for grapeseed oil. The predominant fatty acid in both seeds was linoleic acid. The iodine value, saponification number and acid value were 116, 248 and 0.97 for melonseed oil and 132, 194 and 1.59 for grapeseed oil. The amino acid profiles of both seed cake proteins were determined and compared with hen’s egg protein.